title: Broadband, polarization-insensitive and wide-angle absorption enhancement of a-Si:H/μc-Si:H tandem solar cells by nanopatterning a-Si:H layer.
abstract: A photonic crystal design that significantly enhances the absorption of tandem thin-film solar cells composed by amorphous and microcrystalline silicon (i.e., a-Si:H/μc-Si:H tandem cell) is proposed. The top junction with a-Si:H is nanopatterned as a one-dimensional photonic crystal. Considering the photocurrent matching, we optimally design the junction thickness and the configuration of the nanopattern; moreover, both transverse electric and magnetic incidences with various illuminating angles are taken into account. Calculations by rigorous coupled-wave approach and finite-element method show that the nanophotonic crystal design can improve the absorption and output photocurrent by over 20%, which shows very low sensitivity to the incident polarization. Moreover, the proposed structure is able to sustain the performance for a very wide angle ranges from 0° to ~80°.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Li
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhang
authors.forename: Zhenhai
authors.initials: Z
authors.lastname: Yang
authors.forename: Aixue
authors.initials: A
authors.lastname: Shang